CN108037430A - A kind of 10kV distribution transformers three-phase partial discharge test system - Google Patents
A kind of 10kV distribution transformers three-phase partial discharge test system Download PDFInfo
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- CN108037430A CN108037430A CN201711139039.1A CN201711139039A CN108037430A CN 108037430 A CN108037430 A CN 108037430A CN 201711139039 A CN201711139039 A CN 201711139039A CN 108037430 A CN108037430 A CN 108037430A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/12—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing
- G01R31/14—Circuits therefor, e.g. for generating test voltages, sensing circuits
Abstract
This application involves system for distribution network of power high potential test for electric equipment technical field, and in particular to a kind of 10kV distribution transformers three-phase partial discharge test system.Existing system needs to repeat test connection, increases experiment work amount, simultaneously because different when the shelf depreciation situation measured during single-phase pressurization is from distribution transformer actual motion so that deviation occurs in result of the test.The application provides a kind of 10kV distribution transformers three-phase partial discharge test system, including signal processing unit and signal monitoring unit；Signal processing unit includes sequentially connected power module, frequency filter, isolating transformer, variable-frequency power sources cabinet, high frequency filter and exciting transformer；Signal monitoring unit includes coupled capacitor module, detection impedance module and the local discharge instrument being connected with each other.Realization monitors the test method of local discharge signal at the same time to 10kV distribution transformer low-voltage power supplies, high pressure three-phase, has saved the time of single-phase test of many times so that result of the test is more accurate.
Description
Technical field
This application involves system for distribution network of power high potential test for electric equipment technical field, and in particular to a kind of 10kV distribution become
Depressor three-phase partial discharge test system.
Background technology
It is to customer power supply, including to general industry user, resident's illumination, the power supply of business, Office Area, 10kV power distribution networks
Most suitable voltage class, China generally use 10kV voltage class to customer power supply.10kV urban power distribution networks are whole electricity
It is largest in net, it is related to the most wide part of area, 10kV power distribution networks become power system power supply ability, electric energy, quality, confession
The final embodiment of the important indicators such as electric reliability.
Shelf depreciation refers to that dielectric in High-Voltage Electrical Appliances under high electric-field intensity effect, occurs between the electrodes not
Perforative electric discharge.The defects of purpose of partial discharge test is discovering device structure and manufacturing process.Such as：The local electricity of insulating inner
Field intensity is excessive；Metal parts has point；Insulation be mixed into impurity or between faulty goods interior metal grounded parts, lead
Be electrically connected between electric body it is bad etc., to eliminate these defects, prevent shelf depreciation to insulation damage.
Its manufacture level and processing quality, existing distribution transformer are examined by the partial discharge test of distribution transformer
Partial discharge test mostly using traditional single-phase pressurization by phase measuring system, but this system needs to repeat experiment to connect
Line, increases experiment work amount, simultaneously because when the shelf depreciation situation measured during single-phase pressurization is with distribution transformer actual motion
It is different so that deviation occurs in result of the test.
The content of the invention
The purpose of the present invention is to solve the partial discharge test by distribution transformer come examine its manufacture level and
Processing quality, the partial discharge test of existing distribution transformer mostly using traditional single-phase pressurization by phase measuring method, still
This method needs to repeat test connection, increases experiment work amount, simultaneously because the shelf depreciation situation measured during single-phase pressurization
It is different during from distribution transformer actual motion so that the problem of deviation occurs in result of the test.
For this reason, an embodiment of the present invention provides following technical solution：A kind of 10kV distribution transformers three-phase shelf depreciation examination
Check system, including signal processing unit and signal monitoring unit；
The signal processing unit includes sequentially connected power module, frequency filter, isolating transformer, variable-frequency power sources
Cabinet, high frequency filter and exciting transformer；The signal monitoring unit includes coupled capacitor module, the detection impedance being connected with each other
Module and local discharge instrument, the coupled capacitor module include three coupled capacitor devices in parallel, the detection impedance module bag
Include three detection impedances.
Alternatively, the shelf depreciation instrument includes four Measurement channels.
Alternatively, the power module includes 380V power supplys.
Alternatively, the signal includes voltage signal and local discharge signal.
Alternatively, the exciting transformer is connected with tested step down side, three coupled capacitors in parallel
Device is connected with tested high voltage side of transformer.
Alternatively, output voltage signal includes 3 times of power-frequency voltage signals after the variable-frequency power sources cabinet frequency conversion.
Technical solution provided in an embodiment of the present invention includes following beneficial effect：The application is by the way that tested transformer is distinguished
It is connected with signal processing unit and signal monitoring unit, stable voltage signal is obtained by signal processing unit and part is put
Electric signal, while voltage signal and local discharge signal are detected by signal monitoring unit, realize and 10kV distribution are become
Depressor low-voltage power supply, high pressure three-phase monitor the test method of local discharge signal at the same time, have saved the time of single-phase test of many times,
And phase insulation performance is examined so that result of the test is more accurate.
Brief description of the drawings
In order to illustrate the technical solution of the embodiments of the present invention more clearly, below will be to needed in the embodiment attached
Figure is briefly described, it should be apparent that, for those of ordinary skills, before not making the creative labor property
Put, other attached drawings can also be obtained according to these attached drawings.
Fig. 1 is a kind of 10kV distribution transformers three-phase partial discharge test system schematic in the embodiment of the present invention；
Fig. 2 is partial discharge test pressurization protocols schematic diagram in the embodiment of the present invention；
Symbolic indication in Fig. 1~2 is：
1- signal processing units, 2- signal monitoring units, 3- power modules, 4- frequency filters, 5- isolating transformers, 6-
Variable-frequency power sources cabinet, 7- high frequency filters, 8- exciting transformers, 9- coupled capacitor modules, 10- detection impedance modules, 11- are locally put
Electric instrument, 12- are tested transformer.
Embodiment
Here exemplary embodiment will be illustrated in detail.Embodiment described in following exemplary embodiment
Do not represent all embodiments consistent with the present invention.On the contrary, they be only with as being described in detail in the appended claims
, the example of the method that some aspects of the invention are consistent.
Below by embodiment, the technical solution of the application is described in further detail.
Referring to Fig. 1, the embodiment of the present invention provides a kind of 10kV distribution transformers three-phase partial discharge test system, including letter
Number processing unit 1 and signal monitoring unit 2；
The signal processing unit 1 includes sequentially connected power module 3, frequency filter 4, isolating transformer 5, frequency conversion
Power cabinet 6, high frequency filter 7 and exciting transformer 8；The signal monitoring unit 2 includes the coupled capacitor module being connected with each other
9th, impedance module 10 and local discharge instrument 11 are detected, the coupled capacitor module 9 includes three coupled capacitor devices in parallel, described
Detecting impedance module 10 includes three detection impedances.
Alternatively, the shelf depreciation instrument 11 includes four Measurement channels.
Alternatively, the power module 3 includes 380V power supplys.
Alternatively, the signal includes voltage signal and local discharge signal.
Alternatively, the exciting transformer 8 is connected with tested 12 low-pressure side of transformer, described three coupling electricity in parallel
Container is connected with tested 12 high-pressure side of transformer.
Alternatively, output voltage signal includes 3 times of power-frequency voltage signals after 6 frequency conversion of variable-frequency power sources cabinet.
Because of the background office required during 10kV dry-type transformers (one of which of 10kV distribution transformers) partial discharge test
Portion's electric discharge is no more than 10pC, and experiment is powered using three-phase alternating current 380V power supplys, after frequency filter 4 filters power module 3
Isolating transformer 5 is inputted, being filtered and isolating reduces background shelf depreciation；
Isolating transformer 5 is exported to variable-frequency power sources cabinet 6, (is usually 3 times by exporting multiple frequence after 6 frequency conversion of variable-frequency power sources cabinet
Power frequency) voltage tremendously high frequency wave filter 7, after filtering again output to exciting transformer 8, finally by exciting transformer 8 export to
Tested transformer 12；
3 coupled capacitor devices of high-pressure side parallel three phase of tested transformer 12, realize voltage and local discharge signal at the same time
Monitoring；
Local discharge signal is followed by being easy to signal into the respective channel of instrument for measuring partial discharge 11 by three detection impedances
Observation and analysis；
After completing test connection, background local discharge signal calibration should be carried out before pressure build-up test, confirms that the part of measurement is put
Electric signal it is true and reliable.
A whole set of pilot system includes 380V power supplys, frequency filter 4, isolating transformer 5, variable-frequency power sources cabinet 6, High frequency filter
Device 7, exciting transformer 8, coupled capacitor module 9, detection impedance module 10, shelf depreciation instrument 11, each equipment concrete function are：
Frequency filter 4 is used to filter out the Hz noise in exchange 380V power supplys, lifts waveform quality；
Isolating transformer 5 is used to carry out isolation processing to exchange 380V power supplys, further reduces Hz noise；
Frequency conversion, the output that variable-frequency power sources cabinet 6 is used for realization to supply voltage and electric current adjust and monitoring；
High frequency filter 7 is used for the filtering that order harmonic frequencies are carried out to double frequency voltage and electric current, filters out high-frequency signal
Interference；
Exciting transformer 8 is used to can be achieved to pressurize to the low pressure of the 10kV distribution transformers of different connection sets；
Coupled capacitor device module 9 is used to integrate voltage divider and coupled capacitor device function, can meet that voltage is supervised at the same time
Survey and local discharge signal monitors；
Detect impedance module 10 and be used for one of indispensable accessory of pulse current method measurement shelf depreciation, it can be achieved that instantaneous local
The pulse current of electric discharge produces pressure drop in detection impedance, feeds back to shelf depreciation instrument and is analyzed；
Shelf depreciation instrument 11 is used to the shelf depreciation electric signal of multiple monitoring passages being converted to digital signal, and through data
The collection of illustrative plates that ellipse or sinusoidal waveform are rendered as after processing is analyzed.
Voltage calculates
Change is done for certain factory model SGB10-1600-10/0.4 10kV, according to national standard GB 1094.11-2007《Electric power becomes
The 11st part dry-type transformer of depressor》Technical requirements, Ur is rated voltage 10kV, then pre- making alive U_1=1.8U_r=
18kV, test voltage U_2=" 1.3U " _ r is down to after continuing 30s, is continued 3min and is carried out measurement of partial discharge, it is desirable to shelf depreciation
Amount is not more than 10pC, and test procedure is referring to Fig. 2.
According to testing equipment parameter and experiment calculation as a result, dry become specified shelves no-load voltage ratio K_1=10000/400=25, excitation
8 no-load voltage ratio K_2=800/310=2.62 of transformer, measurement winding no-load voltage ratio K_3=3.
(1) pre- making alive U_1 is line voltage, then each phase-to-ground voltage U^'=U_1/ √ that three-phase divider measures under U_1
Each phase-to-ground voltage U^ "=U_2/ √ 3=13/ that three-phase divider measures under 3=18/ √ 3=10.4kV, test voltage U_2
√ 3=7.5kV.
(2) under pre- making alive U_1, do and become low pressure input line voltage U_ab=U_bc=U_ca=U_1/K_1=18000/
25=720V；Under test voltage U_2, do and become low pressure input line voltage U_ab=U_bc=U_ca=U_2=U_2/K_1=
13000/25=520V.
(3) under pre- making alive U_1,6 output line voltage U_ab^'=U_ab^'=U_ab^'=U_ab/K_ of variable-frequency power sources cabinet
2=720/2.62=274V phase-to-ground voltage U_ao^'=U_bo^'=U_co^'=(U_ab^')/√ 3=274/ √ 3=
158.2V；Under test voltage U_2,6 output line voltage U_ab^ " of variable-frequency power sources cabinet=U_bc^ "=U_ac^ "=U_ab/K_2=
520/2.62=198V, phase-to-ground voltage U_ao^ "=U_bo^ "=U_co^ "=(U_ab^')/√ 3=198/ √ 3=
114.3V。
(4) under pre- making alive U_1, variable-frequency power sources control cabinet high-pressure side monitoring voltage U_ab^ " '=U_bc^ " '=U_ac
^ " '=(U_ab^')/K_3*K_1=274/3*25=2.28kV；Under test voltage U_2, variable-frequency power sources control cabinet high-pressure side prison
Survey voltage U_ab^ " "=U_bc^ " "=U_ac^ " "=(U_ab^ ")/K_3*K_1=198/3*25=1.65kV.
Signal analysis
This three-phase partial discharge test employs two groups of wave filters, one group of three-phase main-frequency filter to be installed at electric power incoming line
Ripple device, background 18.3pC is down to 12.7pC before power supply is closed a floodgate.Another group is high frequency filter, and combined floodgate rear backdrop 12.7pC is dropped
Within as low as 4.69pC, the 10pC for reaching testing standard requirement.
Three-phase background is 4.69pC, 3.85pC, 4.11pC respectively after power supply closes a floodgate；Shelf depreciation under 1.3U_r test voltages
Measuring the three-phase partial discharge quantity of monitoring is respectively：9.35pC, 8.75pC, 9.02pC, be respectively less than regulatory requirements 10pC, do become three
Phase partial discharge test is qualified.
The application passes through letter by the way that tested transformer 12 is connected with signal processing unit and signal monitoring unit respectively
Number processing unit obtains stable voltage signal and local discharge signal, while by signal monitoring unit to voltage signal drawn game
Portion's discharge signal is detected, and is realized and is monitored local discharge signal at the same time to 10kV distribution transformer low-voltage power supplies, high pressure three-phase
Test method, saved the time of single-phase test of many times, and examined phase insulation performance so that result of the test is more accurate
Really.
The above is only the embodiment of the embodiment of the present invention, make those skilled in the art consider specification and
After putting into practice the invention applied here, other embodiments of the present invention will readily occur to.This application is intended to cover appointing for the application
What variations, uses, or adaptations, these variations, uses, or adaptations follow the general principle of the present invention simultaneously
The common knowledge or conventional techniques in the art do not invented including the application.Description and embodiments are considered only as
Exemplary, the true scope and spirit of the application are pointed out by following claim.
It should be appreciated that the application is not limited to the technical solution being described above, and can not depart from
Its scope carries out various modifications and change.Scope of the present application is only limited by appended claim.
Claims (6)
- A kind of 1. 10kV distribution transformers three-phase partial discharge test system, it is characterised in that including signal processing unit (1) and Signal monitoring unit (2)；The signal processing unit (1) include sequentially connected power module (3), frequency filter (4), isolating transformer (5), Variable-frequency power sources cabinet (6), high frequency filter (7) and exciting transformer (8)；The signal monitoring unit (2) includes what is be connected with each other Coupled capacitor module (9), detection impedance module (10) and local discharge instrument (11), the coupled capacitor module (9) include three Coupled capacitor device in parallel, the detection impedance module (10) include three detection impedances.
- 2. the system as claimed in claim 1, it is characterised in that the shelf depreciation instrument (11) includes four Measurement channels.
- 3. the system as claimed in claim 1, it is characterised in that the power module (3) includes 380V power supplys.
- 4. such as system according to any one of claims 1 to 3, it is characterised in that the signal includes voltage signal and part Discharge signal.
- 5. system as claimed in claim 4, it is characterised in that the exciting transformer (8) and tested transformer (12) low pressure Side is connected, and three coupled capacitor devices in parallel are connected with tested transformer (12) high-pressure side.
- 6. system as claimed in claim 5, it is characterised in that output voltage signal bag after variable-frequency power sources cabinet (6) frequency conversion Include 3 times of power-frequency voltage signals.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201711139039.1A CN108037430A (en) | 2017-11-16 | 2017-11-16 | A kind of 10kV distribution transformers three-phase partial discharge test system |
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| CN201711139039.1A CN108037430A (en) | 2017-11-16 | 2017-11-16 | A kind of 10kV distribution transformers three-phase partial discharge test system |
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Cited By (6)
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| CN108896885A (en) * | 2018-07-11 | 2018-11-27 | 云南电网有限责任公司电力科学研究院 | A kind of distribution transformer shelf depreciation and over-voltage monitoring equipment |
| CN109858074A (en) * | 2018-12-13 | 2019-06-07 | 云南电网有限责任公司电力科学研究院 | A kind of simulation method of the transformer oil flow surge based on finite volume method |
| CN110161383A (en) * | 2019-04-30 | 2019-08-23 | 云南电网有限责任公司电力科学研究院 | A kind of detection device for partial discharge of switch cabinet |
| CN110596544A (en) * | 2019-09-04 | 2019-12-20 | 国网四川省电力公司电力科学研究院 | Partial discharge test platform under power cable frequency conversion series resonance |
| CN110658423A (en) * | 2018-06-29 | 2020-01-07 | Abb瑞士股份有限公司 | Partial discharge monitoring system with compatibility function for voltage indication system |
| CN111505470A (en) * | 2020-06-19 | 2020-08-07 | 国网北京市电力公司 | High-power supply filter in partial discharge test |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN110658423A (en) * | 2018-06-29 | 2020-01-07 | Abb瑞士股份有限公司 | Partial discharge monitoring system with compatibility function for voltage indication system |
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| CN110596544B (en) * | 2019-09-04 | 2022-02-11 | 国网四川省电力公司电力科学研究院 | Partial discharge test platform under power cable frequency conversion series resonance |
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| CN111505470B (en) * | 2020-06-19 | 2022-03-01 | 国网北京市电力公司 | High-power supply filter in partial discharge test |
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Application publication date: 20180515 |